1. Field of the Invention
The present invention relates generally to Ethernet physical layer devices and, more particularly, to an Ethernet physical layer device using time division duplex.
2. Introduction
Ethernet is one of the most successful and long lasting designs for data communications over wired networks. Ethernet physical layer device (PHY) specifications have evolved significantly. The most recent formats for 10 Mbps and 100 Mbps Ethernet PHYs use two pairs of twisted cables, while for 1 Gbps, four pairs of twisted cables are used as specified in the IEEE 802.3 standard.
In the existing telephony wirings, a single twisted pair is often available. The wirings may be tapped to provide services at multiple points. These tapped wires, which are commonly referred to as “bridged taps,” cause strong reflections or echoes affecting signal quality. Coaxial cable networks, which are mainly used for TV signal distribution, are also single pair. These coaxial cables, which are often tapped using splitters for multi-room services, cause strong reflections.
What is needed therefore is a mechanism for sending standard Ethernet data packets over a single-pair cable in a manner that can leverage integrated mixed signal silicon devices and signal processing techniques developed for existing Ethernet PHYs.